Contributions by Dorfman and Samuelson in 1986 and van Suntum in 1988 endorse Thünen's famous tombstone formula apunder his specific assumptions. Nonetheless Thünen's proce-dure to achieve the result is a subject of controversy to this day. This paper attempts to follow Thünen's approach step by step. For this purpose Thünen's deduction of the tombstone for-mula is first represented graphically. In a second step an algebraic reconstruction of the prob-lem is contrasted with Thünen's approach. Confirmations of the tombstone formula as well as critiques of the last decades are briefly commented against this background.